1. Field of the Invention
The present invention relates generally to medical devices and procedures and, more particularly, to devices and procedures for treating hyperopia and presbyopia of the eye using laser tunneling.
2. Description of Related Art
A common ophthalmologic condition relating to focusing disorders is known as hyperopia. Hyperopia, or farsightedness, relates to an eyesight refractive abnormality whereby near objects appear blurred or fuzzy as a result of light rays being brought to focus behind the retina of the eye. One variation of hyperopia is presbyopia, which typically is associated with a person's lack of capacity to focus at near distances and which tends to develop and progress with age. Regarding this progression, presbyopia is thought to advance as the eye progressively loses its ability to accommodate or focus sharply for near vision with increasing age of the person. Accordingly, the condition of presbyopia generally signifies a universal decrease in the amplitude of accommodation of the affected person.
Hyperopia can be treated surgically using techniques including corneal interventions, such as reshaping a surface curvature of the cornea located inside of the limbus area, and non-corneal manipulations, such as altering properties of the sclera located outside of the limbus area, ciliary muscle, zonules, or lens. An example of the former treatment can comprise ablating the surface of the cornea itself to form a “multifocal” arrangement (e.g., distance vision in one eye and reading vision in another eye according to a treatment plan referred to as monovision) facilitating viewing by a patient of both near and far objects, and an example of the latter treatment can comprise introducing kerfs into portions of the sclera to thereby increase accommodation. An example of the latter treatment is disclosed in U.S. Pat. No. 6,263,879, wherein incisions are formed in the sclera beneath the conjunctiva.